+1 to constitution, +1 to dexterity, +2 to charisma.

As the offspring of human and a Vampire that was born, not made, the blood of the undead and living mix together inside you to create a cocktail of weaknesses and strengths. Thankfully, there is more of the latter than the former. As a mixed blood, The more... classic weaknesses of a vampire do not impose their effects on your humanoid blood. Garlic, Sunlight and denying verbal entrance to a location are useless against you, with the instant kill of a steak through the heart still being incredibly fatal, will not paralyse you to the spot. You need not possess a coffin to rest and finally, you need not drink with an eternal thirst. and with your undead nature, necrotic damage is but an annoyance when compared to the more fatal sources of harm in the world. Sleeping is not a ture issue for you, only requiring 4 hours of uninterrupted rest compared to the mortal 8

HOWEVER

This sadly does not mean you are uneffected by your parent's blood. While being able to cross it just fine, Water does and will burn you on contact, dealing 1d4 acid damage for each five feat of movement spent within water of knee height or higher. As a cursed undead, Radiant energies pose a mortal threat to your non-mortal existence, posing a weakness against such energies within your blood. And holy items, even if your soul is as pure as snow, will pose a very REAL threat to your continued health. churches, temples or otherwise will cause you great discomfort, posing one level of exhausting as long as you tread on hallowed or sanctified ground. 

Due to your undead nature, and your unnatural sense, you gain a mutated sense of darkvision called 'Aura sense'. For up to 60 feet in distance, you can see in darkness as if through azure tinted glasses, everything showing up in shades of blue. However, the same cannot be said for creatures that possess blood within them. As a bonus action, you can dismiss or bring about a change in your vision, shifting the world into shades of blue except for creatures that possess a heart or cardiovascular system.  Depending on the creature's type, they will possess a haze around their body, with most living material plane entities possessing a green aura to show their health and vibrant lives.

Undead will seem grey, lifeless, standing out amidst the world.

Those of celestial will garner a pure white cloak around their forms, with the abyssal and infernal possessing a dark black for their corrupted souls. 

Fey and their darker counterparts will come across as a strange mix of gold and teal, showing how their energies mix with the land

Abborations will don a cloak of rich, otherworldly violet, their forms strange to the world they walk 

Primordial or elemental entities will possess the aura of green, tinted with the elemental colouration they are connected to. 

and Finally, the monstrosities of the world... a solid red. Horrifying creatures that stand out from the world's natural order. 

 When using this Ability, your eyes will glow as scarlet as the life fluid you feast on. 

As the offspring of a vampire, you cannot always be expected to go the route of swords and spells. sometimes it's best to get up close and personal with your prey, allowing you to use your 1d6+dex Claws (prof + dex to hit). But when harmed and desperate, you may grab a willing creature or perhaps a unwilling creature and drain their fluids for your own consumption.

When drinking another's blood, you can impose a charisma saving check on them or have them submit to your thirst as you sink your fangs into them for 1d8 + dex  (2d8 at 5th level, 3d8 at 11th, 4d8 at 17th) necrotic damage, gaining the amount back in hp. However, as you cannot handle the copious amounts of blood as your parent, this can only be done once per short rest, leaving you time to recover after drinking the blood of another. You cannot mesmerise a target that is blind and deaf, or immune to charm. 

(DC= Charisma + Proficiency+8)

due to your unnatural body and beyond mortal limits, you possess the capabilities of a vampire's strange yet superior agility. Able to jump for 3x the height and length of the common human, you are a master of manoeuvring yourself from place to place.